Yeah, i am open for new ideas, but it is just a bad idea to use something like X icon for something like that purpose, and then naming the map with "restricted" name too, that is just ultra confusion. ask anyone (other than your friends), and they would agree me.
The maps doesnt need anything "some more" / "something different" to be accepted. only thing that matters is the path, if GFX is bad it doesnt mean map is bad (or good). if you break the very basic sense, like you did with the X's, then you are going in the wrong direction. Dont try to make TV screen into a circle just because nobody has done it before, it doesnt mean its a good idea. if you get my point.
However, if those X's were different, almost like a texture of some sort of machine thingy, like 3d'ish look, then it would be ok since there cant be confusion anymore. i think.
(I just hope you never go to Microsoft team, because in the future we would see a mouse cursor that looks exactly like a warning triangle. but hey, we need to be open minded! right?
)